The present invention relates to novel fluorine-containing cyclic compounds and polymer compounds using the same and particularly to resist materials of vacuum ultraviolet region, which have recently and actively been studied, and pattern forming processes.
Fluorine-containing compounds have been used or developed in a wide applied field centered at advanced material fields due to characteristics possessed by fluorine, such as water repellency, oil repellency, low water absorption, heat resistance, weather resistance, corrosion resistance, transparency, photosensitivity, low refractive index, and low dielectric property. In particular, in the case of utilizing characteristics of transparency behavior in each wavelength, they are applied to the coating field. There are active researches and developments going on in the fields such as anti-reflection films, to which low refractive indexes and visible light transparency have been applied, optical devices, to which transparency in long wavelength band (optical communication wavelength band) has been applied, and resist materials, to which transparency in ultraviolet region (particularly vacuum ultraviolet wavelength region) has been applied. As a common high-molecule design in these applied fields, it is tried to achieve good adhesion to substrate and high glass transition point (hardness), while achieving transparency in each wavelength for use by introducing as many fluorine atoms as possible. There are various proposals of increasing transparency at each wavelength by increasing the fluorine content as material design. However, there are few examples on improving fluorine-containing monomers themselves in hydrophilicity and adhesion and on obtaining high Tg. Recently, in next generation F2 resist field of vacuum ultraviolet region, there were reports on a hydroxyl-containing fluorostyrene (see T. H. Fedynyshyn, A. Cabral et al., J. Photopolym. Sci. Technol., 15, 655-666 (2002)) and on a hydroxyl-containing fluoronorbornene compound (see Ralph R. Dammel, Raj Sakamuri et al., J. Photopolym. Sci. Technol., 14, 603-611 (2001)). Thus, there was emerged an idea of containing fluorine and making polarity of hydroxyl group coexistent. However, compatibility between transparency in ultraviolet rays and etching resistance is still insufficient, and there exist many factors to be improved. Furthermore, with respect to polymerizability too, conventional fluorine-containing norbornene compounds have an electron-attracting group, such as fluorine atom and trifluoromethyl group, directly on the norbornene ring, thereby lowering electron density of a polymerizable double bond. Thus, there were problems of low yield and insufficient molecular weight in synthesis of polymer compounds. Thus, these conventional compounds are not necessarily sufficient in capability, and there has been a demand for creating a novel monomer or its raw material capable of efficiently providing further improved polymer compounds.